1. Field
The present disclosure relates generally to transportation systems and in particular to a method and apparatus for managing a transportation system. Still more particularly, the present disclosure relates to a computer implemented method, apparatus, and computer usable program code for simultaneously generating vehicle routing, vehicle scheduling, and crew scheduling for a transportation system.
2. Background
Transportation systems are used to move people and/or goods from one place to another. Transportation systems also may be referred to as transportation networks. A transportation system may include an infrastructure. This infrastructure may include transport networks and nodes. A transportation network may be, for example, roads, railroads, airways, waterways, canals, and other suitable mediums for moving vehicles from one location to another location. Nodes include, for example, airports, railway stations, trucking stations, seaports, and other suitable locations. Some of these nodes are also referred to as depots. A depot is a node where vehicles and drivers are based. Depots are the starting and ending nodes for vehicle and crew schedules.
Vehicles are used to transport items, such as goods and/or people, between nodes. These items may be transported on vehicles, such as, for example, trucks, automobiles, buses, trains, and aircraft.
Operations deal with the manner in which vehicles are operated in a transportation network. The operations may be constrained by the infrastructure. Further, a set of rules or policies may determine what operations may be legally performed within a transport system. These rules include, for example, laws, codes, regulations, agreements, licenses, and other suitable rules.
In managing the transportation of items to different locations, one or more objectives may be present. One objective includes the cost to transport all the items.
Vehicle routing, vehicle scheduling, and crew scheduling are some of the problems often faced by planners of transportation systems. Examples of such transportation systems include: metropolitan mail delivery; intra-state parcel delivery; distribution of consumer goods from warehouses to retail outlets; and transportation of cargo and passengers by aircraft in theatres of war. The challenges faced by these and other types of transportation systems involves finding a minimum cost for a set of mutually compatible vehicle routes, vehicle and crew schedules to transport a set of specific transportation requests. Examples of transportation requests include: picking up and dropping off passengers at different locations; transporting cargo between specific origins and destinations; picking up and delivering mail and parcels between mail sorting and processing facilities.
Numerous solutions and programs are currently available to generate a plan for transporting items within a transport system. Some solutions first construct a set of vehicle routes. After the set of vehicle routes are constructed, a set of crew schedules are built to cover the vehicle routes. Further, vehicles are assigned to the set of vehicle routes to produce vehicle schedules.
These techniques may use various algorithms or processes. For example, algorithms using various meta-heuristic techniques like tabu search and algorithms based on linear and integer programming theory may be employed to generate a plan for transporting items within a transportation system. Although these different processes provide plans for transporting items, these different processes do not always provide the most desirable or least cost transportation plans. Therefore, it would be advantageous to have an approved method and apparatus that overcomes the above described problems.